Negative stiffness can be generated by non-linear behavior. For instance, simple and widely used non-linear structures that can generative negative stiffness include snap-through beams, buckling beams, over-rotation, and rolling or sliding contact between components. Non-linear structures that exhibit both positive and negative stiffness are potentially useful in a variety of mechanical design applications. For instance, as illustrated in FIG. 1, a negative stiffness element 10 (e.g., a buckling-type beam than can exhibit non-linear behavior) can be combined with a positive stiffness element 11, such as a spring, to provide a structure having zero or quasi-zero stiffness (QZS) over a range of displacements. The quasi-zero stiffness of the structure may be used to isolate another object 12 (e.g. a structure, device, package, and/or an instrument) from unwanted vibrations because the transmission of vibrations through systems of very low stiffness is minimal. However, these conventional isolating structures tend to be unstable in their isolating mode and are more easily utilized for their damping and shock isolation abilities, because manufacturing technologies and techniques are typically not accurate enough to create a QZS structure that does not require daily tuning. Additionally, conventional QZS structure may require very fine adjustment to achieve even moderate performance, which is both time-consuming and labor intensive. Additionally, very low (e.g., quasi-zero) stiffness can be theoretically obtained with very long linear springs, but such long springs are not practical in many applications due to size constraints.